On 2 January you are on a course of 094° T at a speed of 20 knots. At 0430 ZT, your DR position is LAT 24° 12' N, LONG 71° 24' W. Determine the zone time of sunrise.
• Use the Nautical Almanac sunrise tables for the correct date and latitude • Apply interpolation between latitudes and/or longitudes if needed • Convert between GMT (UT), zone time (ZT), and apply the correct zone description (ZD) for the longitude
• What latitude and longitude should you use to enter the sunrise tables: the DR at the given time, or some adjusted position? Why? • Once you obtain the sunrise time in GMT/UT from the almanac, how do you correctly convert it to zone time based on your longitude? • Is there any need to correct for your run between a standard meridian and your actual longitude, and in what direction would that change the local sunrise time?
• Be sure you are using the correct date (remember the almanac date is in GMT/UT) • Verify the zone description (ZD) from your longitude (east is plus, west is minus from GMT) • Double-check whether any longitude correction to the tabulated sunrise time is required and its sign before matching to the multiple-choice answers
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